const path = require('path');
const webpack = require('webpack');
const TerserPlugin = require('terser-webpack-plugin');
const CopyWebpackPlugin = require('copy-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const WextManifestWebpackPlugin = require('wext-manifest-webpack-plugin');
const ForkTsCheckerWebpackPlugin = require('fork-ts-checker-webpack-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const viewsPath = path.join(__dirname, 'views');
const sourcePath = path.join(__dirname, 'source');
const destPath = path.join(__dirname, 'extension');
const targetBrowser = process.env.TARGET_BROWSER;

const getExtensionFileType = (browser) => {
  if (browser === 'opera') {
    return 'crx';
  }
  if (browser === 'firefox') {
    return 'xpi';
  }
  return 'zip';
};

const commonConfig = {
  // devtool: false, // https://github.com/webpack/webpack/issues/1194#issuecomment-560382342

  stats: {
    all: false,
    builtAt: true,
    errors: true,
    hash: true,
  },

  // mode: nodeEnv,

  entry: {
    manifest: path.join(sourcePath, 'manifest.json'),
    // background: path.join(sourcePath, 'Background', 'index.ts'),
    // contentScript: path.join(sourcePath, 'ContentScript', 'index.ts'),
    popup: path.join(sourcePath, 'Popup', 'index.tsx'),
    // options: path.join(sourcePath, 'Options', 'index.tsx'),
  },

  output: {
    path: path.join(destPath, targetBrowser),
    filename: 'js/[name].bundle.js',
  },

  resolve: {
    extensions: ['.ts', '.tsx', '.js', '.json'],
    alias: {
      'webextension-polyfill-ts': path.resolve(
        path.join(__dirname, 'node_modules', 'webextension-polyfill-ts')
      ),
    },
  },

  module: {
    rules: [
      {
        type: 'javascript/auto', // prevent webpack handling json with its own loaders,
        test: /manifest\.json$/,
        use: {
          loader: 'wext-manifest-loader',
          options: {
            usePackageJSONVersion: true, // set to false to not use package.json version for manifest
          },
        },
        exclude: /node_modules/,
      },
      {
        test: /\.(js|ts)x?$/,
        loader: 'babel-loader',
        exclude: /node_modules/,
      },
      {
        test: /\.(le|c)ss$/,
        use: [
          {
            loader: MiniCssExtractPlugin.loader, // It creates a CSS file per JS file which contains CSS
          },
          {
            loader: 'css-loader', // Takes the CSS files and returns the CSS with imports and url(...) for Webpack
            options: {
              sourceMap: true,
            },
          },
          {
            loader: 'postcss-loader',
            options: {
              postcssOptions: {
                plugins: [
                  [
                    'autoprefixer',
                    {
                      // Options
                    },
                  ],
                ],
              },
            },
          },
          {
            loader: "less-loader",
            options: {
              lessOptions: {
                javascriptEnabled: true,
              },
            },
          },
        ],
      },
    ],
  },

  plugins: [
    // Plugin to not generate js bundle for manifest entry
    new WextManifestWebpackPlugin(),
    // Generate sourcemaps
    // new webpack.SourceMapDevToolPlugin({ filename: false }),
    new ForkTsCheckerWebpackPlugin(),
    // environmental variables
    new webpack.EnvironmentPlugin(['NODE_ENV', 'TARGET_BROWSER']),
    // delete previous build files
    new CleanWebpackPlugin({
      cleanOnceBeforeBuildPatterns: [
        path.join(process.cwd(), `extension/${targetBrowser}`),
        path.join(
          process.cwd(),
          `extension/${targetBrowser}.${getExtensionFileType(targetBrowser)}`
        ),
      ],
      cleanStaleWebpackAssets: false,
      verbose: true,
    }),
    new HtmlWebpackPlugin({
      template: path.join(viewsPath, 'popup.html'),
      inject: 'body',
      chunks: ['popup'],
      hash: true,
      filename: 'popup.html',
    }),
    // new HtmlWebpackPlugin({
    //   template: path.join(viewsPath, 'options.html'),
    //   inject: 'body',
    //   chunks: ['options'],
    //   hash: true,
    //   filename: 'options.html',
    // }),
    // write css file(s) to build folder
    new MiniCssExtractPlugin({ filename: 'css/[name].css' }),
    // copy static assets
    new CopyWebpackPlugin({
      patterns: [{ from: 'source/assets', to: 'assets' }],
    }),
  ],

  optimization: {
    minimize: true,
    minimizer: [
      new TerserPlugin({
        parallel: true,
        terserOptions: {
          format: {
            comments: false,
          },
        },
        extractComments: false,
      }),
      new OptimizeCSSAssetsPlugin({
        cssProcessorPluginOptions: {
          preset: ['default', { discardComments: { removeAll: true } }],
        },
      })
    ],
  },
};

module.exports = {
  getExtensionFileType,
  commonConfig,
}
